Various 7.1 Clean-up Fixes

[michael-hawker]

Fixes #4210 and Fixes #4158

Cleans up sample for #4248 (though underlying issue remains to be figured out later).

Fixes a sample and cleans-up a few items we missed in our nuget packages. Just need to validate output from CI, but should be fairly straight-forward.

PR Type

What kind of change does this PR introduce?

• Documentation content changes
• Sample app changes

What is the current behavior?

TTB Sample was binding to the internal collection instead of showing binding to a developer provided collection.

Some new features were missing from the NuGet package info.

What is the new behavior?

Fixed! 🎉

PR Checklist

Please check if your PR fulfills the following requirements:

• Tested code with current supported SDKs
• New component
  • Pull Request has been submitted to the documentation repository instructions. Link:
  • Added description of major feature to project description for NuGet package (4000 total character limit, so don't push entire description over that)
  • If control, added to Visual Studio Design project
• Sample in sample app has been added / updated (for bug fixes / features)
  • Icon has been created (if new sample) following the Thumbnail Style Guide and templates
• New major technical changes in the toolkit have or will be added to the Wiki e.g. build changes, source generators, testing infrastructure, sample creation changes, etc...
• Tests for the changes have been added (for bug fixes / features) (if applicable)
• Header has been added to all new source files (run build/UpdateHeaders.bat)
• Contains NO breaking changes

Other information

[ghost]

Thanks michael-hawker for opening a Pull Request! The reviewers will test the PR and highlight if there is any conflict or changes required. If the PR is approved we will proceed to merge the pull request 🙌

[ghost]

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